title: Mutagenic effects of combinations of chemical carcinogens and environmental pollutants in mice as shown by the micronucleus test.
abstract: The effects of combinations of the chemical carcinogens, dimethylnitrosoamine (DMN) or N-methyl-N'-nitro-N'-nitrosoguanidine (MNNG), with the environmental pollutants, cadmium (Cd) or polychlorinated biphenyls (PCB) were examined by Schmidt's micronucleus method with ddY strain mice. DMN had a positive mutagenic effect by oral administration, with a dose response between 25 and 100 mg/kg body weight. MNNG gave a slight positive, though not consistent result, and seemed to be more sensitive at an earlier stage after administration of the drug. Cd was given for up to 7 days in drinking water as a solution of CdCl2 at concentrations of 3, 30 or 300 ppm as Cd. PCB was administered orally at 100 mg/kg daily for 6 days as a solution in corn oil, or subcutaneously injected in ethanol. Neither Cd nor PCB gave positive results in the micronucleus test. However, a synergistic positive effect of Cd with DMN was seen, but PCB with either of these nitrosamines was not positive.
mesh_terms: D000818:Animals; D001853:Bone Marrow / Q000187:drug effects; D002104:Cadmium / Q000494:pharmacology*; D002273:Carcinogens / Q000494:pharmacology*; D002467:Cell Nucleus / Q000187:drug effects; D004128:Dimethylnitrosamine / Q000494:pharmacology; D004357:Drug Synergism; D004912:Erythrocytes / Q000648:ultrastructure; D008769:Methylnitronitrosoguanidine / Q000494:pharmacology; D051379:Mice; D009152:Mutagenicity Tests / Q000379:methods*; D011078:Polychlorinated Biphenyls / Q000494:pharmacology*
chemical_list: D002273:Carcinogens; D002104:Cadmium; D008769:Methylnitronitrosoguanidine; D011078:Polychlorinated Biphenyls; D004128:Dimethylnitrosamine